Interesting question... not sure how you would even measure such a thing?

I've seen West Coast Customs' TV show where they've had custom glass made, they took a sheet of alloy the right thickness, cut it to the right shape and rolled the right curvature into it, before sending it to a glass manufacturer for them to copy.

This subject is far more complex than I had imagined. The side glass has a twist to it end to end also.

I cut a template of the curve of a Torana window and tried it against a few other cars, HZ, a 90's Ford and a few others. Funnily enough the car with the closest match of the top to bottom curve so far is a 2009 Mercedes CLC 200.